Frame structure of dynamoelectric machines



Nov. 16, 1948. F. J. JOHNS FRAME-STRUCTURES OF DYNAMOELECTRIC MACHINESFiled Aug. 28, 1947 INVENTOR Jljkk ATTORNEY Francis JJd/Ins.

Patented Nov. 16, 1948 UNITED STATES PATENT DFFICE FRAME STRUCTURE OFDYNAMOELECTRIC MACHINES Application August 28, 1947, Serial No. 771,015

20 Claims.

My invention relates to a novel structural assembly for thestator-members of large squirrelcage motors or other dynamo-electricmachines, in which various advantages are combined.

An object of my invention is to provide a stator member construction inwhich an annular ventilating-space is economically provided, in whichair-obstructions are minimized, weight is reduced, and strength ismaintained.

With the foregoing and other objects in view, my invention consists inthe machines, constructions, combinations, parts and methods of assemblyand operation, as subsequently described and claimed, and illustrated inthe accompanying drawing, wherein:

Figure 1 is a longitudinal sectional view or a EGO-horsepower, 4 pole,to cycle, polyphase squirrel-cage motor, embodying my invention bl] wayof illustration, the section-plane being indicated at I-I in Fig. 2; and

Fig. 2 is a transverse sectional view of the machine, the plane beingindicated by the line II-II in Fig. l. 4

My invention is particularly applicable, as shown, to a horizontal-shaftmachine having double-end ventilation, that is, a machine in which theventilating-air is drawn into the machine from both ends thereof, and isdischarged laterally of the machine, as will be subsequently described.

The illustrated machine essentially has a stator-member 3 and arotor-member B, the latter being mounted on a horizontal shaft o. Thestator-member 3 comprises a stack of annular stator-punchings 6 having asubstantially cylindrical outer periphery l, and having a bore 3 whichdefines an air gap surrounding the rotormember' l: Stator-windings 9 arecarried by the stator-punchings 6, near the bore thereof.

In accordance with my invention, the outer periphery l of thestator-punchings 6 is engaged by a plurality of radially thickpunching-holding frame-bars H, H and i3, as shown in Fig. 2. Theseframe-bars extend axially across the outer periphery of the stack ofstator-punchings, and they also extend beyond both ends of the stack, asshown at M in Fig. l. The radial thickness of these punching-holdingframe-bars ll, l2 and i3 is equal to the radial thickness of the annularventilating-space H which is to be provided around the outer peripheryof the stator-punchings, as will be subsequently described.

Since these radially thick punching-holding frame-bars ll, 12 and I3close the annular ventilating-space l against any circumferentialmovement of air past any one of said bars, it is quite desirable thatthe number of these radially thick frame-bars should be limited to asmall number, such as two or three, or possibly four. Since it isdesirable that outlet-openings it shall be provided, along each side ofthe stator-frame, below the center-line ll of the stator-member, it isdesirable that one of these radially-thick frame-bars, such as the barll, shall be placed at the top of the stator-punchings 6, where nocircumferential air-flow is needed; and it is further essential that noother radially thick framebar shall be provided above a point which isbelow the level of the outlet-opening it which discharges air from thetop portion of the machine, along each side of the machine. Thus, in thelilustrated construction, as shown in Fig. 2, the radially-thickframe-bars H and i2, which are not at the top of the machine, aredisposed at points which are partway up on the underside of thestator-punchings i, that is, below the center-line ll of the statorpunchings.

The disposition of one of the frame-bars it at the top center of themachine is advantageous in providing an anchorage for two lifting-ringsi8, which are provided for the motor. This top frame-bar it is thusadvantageously a solid bar of approximately square or rectangular shape.The other two radially-thick frame-bars H and it need not be solid, butmay advantageously be Each end-bracket 2i has a bearing-member 22 forsupporting the rotor-shaft 5, and has also one or more inlet-openings 23for ventilating-air. On the inside, each end-bracket 2! is also providedwith baiile-means 24, for cooperating with rotormember fan-means whichare provided in the form of blower-blades 25 which are cast integrallywith the squirrel-cage winding 26 of the rotor-member 4, theseblower-blades 25 being provided at each end of the rotor-member.

Each of the annular frame-rings 20 has a substantially annular outerperiphery 27 which is substantially flush with the outer surfaces of thethick frame-bars ll, l2 and I3. A sheet-like top enclosure-member 28 isprovided, which extends over the top frame-bar II, and the top portionsof the two frame-rings 20, for defining an upper annularventilating-space l5U, between said top enclosure-member 28 and theperiphery 1 of the stator-punchlngs 6. A sheet-like bottomenclosure-member ie is also provided, which ex= closure-members 28 and29 respectively, as shown in Fig. 2, the air-flow being indicated by thearrows. In the illustrated iorm of embodiment of my invention, these twooutlet-openings it and 30 are in the vicinity of the lowermost thick.frame-bars I2 and it, respectively, the outletopemngs it being above thebars 822 and iii, while the outlet-openings lit are below the same. Theadvantage of providing the upper outlet-=opening is below thecenter-line ll of the machine is that it can discharge its airdownwardly so that the machine will be drip-proof.

Since the upper and lower enclosure-members 28 and 29 do not take anysubstantial part of the weight of the statcr member, they may be ofrelatively light plates, in a fabricated construction. Nevertheless,with respect to the rigidity of the complete stator-assembly, these topand bot tom enclosure-plates 23 and 29 contribute considerable rigidityto the entire assembly.

It is desirable that there shall be at least one radially thick, axiallyextending frame-bar ii, placed at the top of the machine, and ingeneral, it is desirable that there shall be no other radially thickbars around the top half of the statorpunchings, or until a point isreached which is considerably below the center-line l7 as indicated bythe positions of the bars 02 and ii} in Fig. 2, In generalit isdesirable, from considerations of structural rigidity, to have one ormore radially thick axially extending framebars, such as IE or ill,located somewhere along the lower portion of the stator-punohings, butpreferably not at any point between the illustrated positions of thebars ii and i2 and the extreme bottom of the punchings, so us not tointerfere with the radial air-movement at this lower part of thestator-frame, as shown by the arrows in Fig. 2.

In large machines, to which my invention is primarily (but notaltogether) applicable, it is not enough to provide such a small numberof axially disposed punching holding frame-bars as the bars H, l2 andto; because if this were the case, the punchings would tend to spreadout axially, at points in between the radially thick frame-bars i2 andi3. ll therefore provide a plurality of radially thin, axially extendingpunching-retaining means, which are shown in the form of frame-bars Si,32 and 3B which preferably have their ends secured to the two framerings23. These thin punching -supporting frame-bars 3|, 32 and 33 aredisposed at a suitable number of intermediate points around thecircumference of the stator-punchings 6, between the thick frame-bars H,H and i3.

Preferably, all six frame-bars Ii, l2, l3, 3|, 32 and 33 are secured tothe end-rings by welding 34, and to the punchings 6 by welding 35.Preferably also, as shown in Fig. 1, each end of the stack ofstator-punchings 6 is engaged by an end plate or ring 36, which iswelded at 31 to the respective frame-bars |2, |3, 3|, 32 and 33.

In the operation of my invention, the rotormounted fan or bloweroperates as a veniii tiiatiug means for causing ventilating-air to enter through the inlet-openings 23 at the respective ends of the machine,and to flow radially outwardly past the end-portions of thestatozo=windings 9 at that end of the machine, and to flow thence radiallyoutwardly past the end portions I4 of the frame-bars ll, l2, i3, 38, 32and 33, where said. frame-bars extend between the end of the stack ofstator-punchings 6 and the frame-ring 23 at that end of the machine. Theventilating-air thus enters the upper and lower annularventilating-spaces |5U and |L, in which the air is free to spread out orflow both axially and circumferentially over the outer periphery l ofthe stator-punchings 6, cooling the same.

It is an important feature of my invention that the ventilating-air isdischarged from the upper annular ventilating-space i6--U, as well asfrom the lower annular ventilating-space iE-L, at axially extendingoutlet-openings it and it, respectively, which are below the center lineill of the machine, so that the top half of the machine is completelyclosed, so as to render the machine drip-proof. To this end, it isnecessary to provide a frame-construction in which there is no radiallythick frame-bar between the top center of the machine, at the positionoccupied by the frame-bar ii, and a point cone siderably below thecenter-line ii, on each side of the machine, as at the positionsoccupied by the frame-bars l2 and i3; but this long arcuate space,between the bar ii and the bar or between the bar it and the bar i3, istoo long to leave the stator punching-stack unrestricted or free tobulge out axially; and hence I provide intermediate thin frame-bars Biand 38, at intermediate points within this space. The thinness of thesebars provides for an ample air-flow space, or radial-displacement,between the flat tops of these thin bars 35 and and the topenclosure-plate 28, so that the circumferential flow of theventilating-air is substan tially unrestricted, as said air flows out ofthe top part of the upper ventilating-space lb-U to the exhaust-openings66 on either side of the machine.

At the extreme bottom edge of the statorpunchings 6, I provide a thirdthin frame-bar 32, but there is no substantial circumferential air-flowat this point, and hence, so far as ventilation is concerned, thisbottom frame-bar 32 can have any radial thickness which may be dictatedby considerations of strength and weight,

A second ventilating-path is also provided, which involves an air-flowfrom the inlet-opem ings 23 in the end-brackets 2|, into the innerportions of the rotor-member 4, where a rotorsplder 40 supports therotor-core or stack of rotor-laminations 4|. The rotor-spider alsoprovides a. plurality of central axial ducts or passageways through therotor-members 4. The rotor-core 4| is provided with a plurality ofradially extending ventilating-openings 42, which are in alignment withcorresponding radial ventilating-openings 43 in the stator-core orpunchings 6.

The rotation of the rotor-member 4 causes this member to act as acentrifugal fan, which draws in ventilating-air, from both ends of themachine, and causes it to flow radially outwardly through the radialventilating-spaces 42 and 43 in the rotor and stator-membersrespectively, whence it discharges into the upper and lower annularventilating-spaces |5U and lB-L, where the air is free to move or expandboth axially and circumferentially, while it ventilates the outerperiphery of the stator-punchings 6, on its way to the lateral outletvents l6 and 30 respectively.

As is common in the art, a foot-assembly 50 is made separately, andsecured to the cylindrical frame-assembly by suitable welding 5|.

My novel frame-construction thus provides a completely fabricatedstator-assembly, all parts of which are made from standard steelsections, involving no burning or other expensive operations. Themachine is drip and splash-proof, rugged, and light in weight.Experience has shown that the machine has unusually good ventilation,due to the fact that there are no obstructions in the necessaryair-paths, thus causing the machine to run appreciably cooler thansimilar machines of the same rating.

While I have illustrated my invention in a single illustrative form ofembodiment, I wish it to be understood that my invention is not limitedto this single precise form, as many changes of substitution, omissionand addition can be made by those skilled in the art, while stillembodying one or more of the essential features of my invention. Idesire, therefore, that the appended claims shall be given the broadestconstruction consistent with their language.

I claim as my invention:

1. A horizontal-shaft dynamo-electric machine having a stator-member anda rotor-member; said stator-member comprising a stack of annularstator-punchings having a substantially cylindrical outer periphery, andhaving a bore defining an air gap surrounding the rotor-member,stator-windings carried by the stator-punchings near the bore thereof, aplurality of radially thick punching-holding frame-bars extendingaxially across the outer periphery of said stack of statorpunchings andextending beyond both ends of the stack, only one of said thickframe-bars being in the region extending from the top to a point belowthe centerline of the stack of stator-punchings on either side thereof,and that one being at the top, an annular frame-ring secured to the endsof the plurality of thick frame-bars at each end of the machine, saidframe-rings having a substantially annular outer periphery which issubstantially flush with the outer surfaces of the thick frame-bars, anend-bracket secured to each frame-ring, each end-bracket having abearingmember for supporting the rotor-member, and having one or moreinlet-openings for ventilating-air, ventilating-means for causingventilating-air to enter through said inlet-openings at the respectiveends of the machine and to flow radially outwardly over the end-turns ofthe sta tor-windings and thence to flow radially outwardly past the endportions of the frame-bars where they extend between the end of thestack of stator-punchings and the frame-ring at that end of the machine,a sheet-like top enclosuremember extending over the top frame-bar andthe top portions of the two frame-rings for defining an upper annularventilating-space between said top enclosure-member and the periphery ofthe punchings, a sheet-like bottom enclosure-member extending over thebottom portions of the two frame-rings for defining a lower annularventilating-space between said bottom enclosure-member and the peripheryof the punchings, outlet-means for providing outlets, be-' bottomenclosure-members, along the sides of the machine, and a plurality ofradially thin, axially extending, punching-retaining means, secured tothe outer periphery of the stack of stator-punchings at intermediatepoints between the thick frame-bars, for preventing axial spreading ofsaid stack while permitting annular airfiow in radial spaces betweensaid thin punchingretaining means and the associated enclosuremember.

2. A horizontal-shaft dynamo-electric machine having a stator-member anda rotor-member; said stator-member comprising a stack of annularstator-punchings having a substantially cylindrical outer periphery, andhaving a bore defining an air gap surrounding the rotor-member,stator-windings carried by the stator-punchings near the bore thereof,three radially thick punchlug-holding frame-bars extending axiallyacross the outer periphery of said stack of stator-punchings andextending beyond both ends of the stack, one of said thick frame-barsbeing at the top, and the other two being at the sides below thecenter-line of the stator-punchings, an annu lar frame-ring secured tothe ends of the three thick frame-bars at 'each end of the machine, saidframe-rings having a substantially annular outer periphery which issubstantially flush with the outer surfaces of the thick frame bars, anend-bracket secured to each frame-ring, each end-bracket having abearing-member for supporting the rotor-member, and having one or moreinlet-openings for ventilating-air, ventilating-means for causingventilating-air to enter through said inlet-openings at the respectiveends of the machine and to flow radially outwardly over the end-turns ofthe stator-windings and thence to how radially outwardly past the endportions of the frame-bars where they extend between the end of thestack of stator-punchings and the frame-ring at that end of the machine,a sheet-like top enclosure-member extending over the top frame-bar andthe top portions of the two frame-rings for defining an upper annularventilating-space between said top enclosuremember and the periphery ofthe punchings, a sheet-like bottom enclosure-member extending over thebottom portions of the two frame-rings for defining a lower annularventilating-space between said bottom enclosure-member and the peripheryof the punchings, outlet-means for providing outlets, in the vicinity ofthe two lowermost thick frame-bars, respectively, for discharging airfrom the ends of the top and bottom enclosure-members, along the sidesof the machine, below the centerline of the statorpunchings, and aplurality of radially thin, axially extending, punching-retaining means,secured to the outer periphery of the stack of stator-punchings atintermediate points between the thick frame-bars, for preventing axialspreading of said stack while permitting annular airflow in radialspaces between said thin punchingretaining means and the associatedenclosuremember.

3. A horizontal-shaft dynamo-electric machine having a stator-member anda rotor-member; said stator-member comprising a stack of annularstator-punchings having a substantially cylindrical outer periphery, andhaving a bore defining an air gap surrounding the rotor-member,stator-windings carried by the stator-punchings near the bore thereof, aplurality of radially thick punching-holding frame-bars extendingaxially across the outer periphery of said stack of statordeco er 07 6puhchings, only one oi sold thicir freme bers be log in. the regionextending from the top to point below the ceuterline of the stock ofstator punchiugs on either side thereof, and that one beiug at the top,on annular to the ends of the plurality of at each end oi the machine,so her/lug at substantially annular outer periphery which issubstoutiolly flush with the outer sur faces of the thicl: frame-hers,end en -bracket secured to each frame-ring, each end-bracket having abearing-member for supporting the rotormeruioer, and having one or moreinlet-openings for ventilating-air, e sheetdike top ehclosure= memberextending over the top Zreme bsr and the top portions of the two fi-emerihgs for de finite" an upper ouhuler vezatiletiug spme be tween saidtop enclosure-member and the periphery oi the punchihgs, a sheetdikebottom enclosure-member extending over the bottom portions oi the twoframe-rings for defining a lower euuuler veritilatingespsce between saidbottom enclosure-member and the periphery of the punchings, outletmee'os for providing outlets, below the center-line of the stetorpurochihgs, for discharging sir from the ends of the top and bottomenclosure-members, along the sides of the mechiue, and a. plurality ofradially thin, axially extending, puncifing-retaining means, secured tothe outer periphery of the stack of stator-punchlugs at intermediatepoints between the thick frame-bars, for preventing axial spreading ofsaid stack while permitting annular air-flow in radial spaces betweensaid this punching-retaming means and the associated enclosure-memher;the stack of stator-punchings having one or more radialventilating-openings therein, and said rotor-member having one or morecorresponding radial ventilating-openings therein, and one or morecentral axial ducts therethrough, whereby ventilating-air flows radiallyoutwardly through said radial ventilating-openings and then distributesitself axially and clrcumferentially in said annular ventilating-spaceson its way outto said outlet-means.

4. A horizontal-shaft dynamo-electric machine having a. stator-memberand a rotor-member;

ing-holding frame-bars extending axially across the outer periphery ofsaid stack of stator-punchlngs, one of said thick frame-bars, being atthe top, and the other two being at the sides below the centerline ofthe stator-punchings, an annular frame ring secured to the ends of thethree thick frame-bars at each end of the machine, said frame-ringshaving a substantially annular outer periphery which is substantiallyflush with the outer surfaces of the thick frame-bars, an end-bracketsecured to each frame ring, each endbrackct having a bearing-member forsupporting the rotor-member, and having one or more inlet-openings forventilating-air, a sheet-like top enclosure-member extending over thetop frame-bar and the top portions of the two framerings for defining anupper annular ventilatingspace between said top enclosure-member and theperiphery of the punchings, a sheet-like bottom enclosure-memberextending over the bottom portions of the two-frame-rings for defininga. lower annular ventilating-space between said bottom enclosme-memberand the periphcry of the puuchihgs, outlet-means for: provid ingoutlets, below the centeriine of the statorpuzichimgs, for dischargingair from the ends of the top and bottom enclosure-=members, along thesides of the machine, and e plurality of re,- dielly thin, axiallyextending punching-retain ing means, secured to the outervperiphery oithe steel: of stotor-puuchihgs at intermediate points betweeu the thicl:frame-bars, for preventing ex= iol spreading of said steel: whilepermitting ennular air-flow "in radial spaces between said thinpunching-retaining means and the associated enclosure-member; the stackoi ststor-punctungs having one or more redial ventilating-openingstherein, and said rotor=member having one or more corresponding redialventilating opehiugs therein, and one or more control axial ductstherethrough, whereby ventilating-air flows rs.- dially outwardlythrough said radial ventilatingopenings and then distributes itselfaxially end circumferentielly in said annular ventilatingspeces on itsWay out to said outlet-means.

5. A horizontal-shaft dynamo-electric machine having a stator-member ands rotor-member; said rotor-member having ran-means for drawing in air,at both ends of the machine, for ventilating purposes; saidstator-member comprising a. stack of annular stator-punchings having a,substantislly cylindrical outer periphery, and having a bore defining anair gap surrounding the rotormember, stator-windings carried by thestatorpunchings near the bore thereof, g plurallty of radially thickpunching-holding frame-bars extending axially across the outer peripheryof said stack of stator-punchings and extending beyond both ends of thestack, only. one of said thick frame-bars being in the region extendingfrom the top to a point below the centerline of the stack ofst-etor-punchings on either side thereof, and that one being at the top,an annular frame-ring secured to the ends of the plurality of thickframe-burs et each end of themachine, said frame-rings having a.substantially annular outer P periphery which is substantially flushwith the outer surfaces of the'thick frame-bars, an endbracket securedto each frame-ring, each endbracket having a bearing-member forsupporting the rotor-member, and having one or more inletopenings forventilating-air, and having bafllemeans carried by each end-bracket forcausing at least some of the inlet-air to enter the rotor fanmeans atthat end of the machine and to flow thence radially outwardly over theend-turns of i the stator-windings and thence to flow radially outwardlypast the end portions of the framebars where they extend between the endof the stack of stator-punchings and the frame-ring at that end of themachine, a sheet-like top enclosure-member extending over the topframe-bar and the top portions of the two frame-rings for defining anupper annular ventilating-space between said top enclosure-member andthe periphery of the punching's, a sheet-like bottom enclosure-memberextending over the bottom portions of the two frame-rings for defininga, lower annular ventilating-space between said bottom enclosure-memberand the periphery of the punchings, outlet-means for providing outlets,below the centerline of the stator-punchlngs, for discharging air fromthe ends of the top and bottom enclosure-members, along the sides of themachine, and a plurality of radially thin, axially extending,punching-retaining means, secured to the outer periphery of the stack ofstator-punch- 9 ings at intermediate points between the thickframe-bars, for preventing axial spreading of said stack whilepermitting annular air-flow in radial spaces between said thinpunching-retaining means and the associated enclosure-member.

6'. A horizontal-shaft dynamo-electric machine having-a stator-memberand a rotor-member; said rotor-member having fan-means for drawing inair, at both ends of the machine, for ventilating purposes; saidstator-member comprising a stack of annular stator-punchings having asubstantially cylindrical outer periphery, and having a bore defining anair gap surrounding the rotormember, stator windings carried by thestatorpunchings near the bore ther'eoi, three radially thickpunching-holding frame-bars extending axially across the outer peripheryof said stack of stator-punchings and extending beyond both ends of thestack, one of said thick frame-bars being at the top, and the other twobeing at the sides below the centerline of the stator-punchings, anannular frame-ring secured to the ends of the three thick frame-bars ateach end of the machine, said frame-rings having a substantially annularouter periphery which is substantially fiush with the outer surfaces ofthe thick framebars, an end-bracket secured to each frame-ring, eachend-bracket having a bearing-member for supporting the rotor-member, andhaving one or more inlet-openings for ventilating-air, and havingbafile-means carried by each end-bracket for causing at least some ofthe inlet-air to enter the rotor fan-means at that end of the machineand to fiow thence radially outwardly over the endturns of thestator-windings and thence to flow radially outwardly past the endportions of the frame-bars where they extend between the end of thestack of stator-punchings and the frame-ring at that end of the machine,a sheet-like top enclosure-member extending over the top framebar andthe top portions of the two frame-rings for defining an upper annularventilating-space between said top enclosure-member and the periphery ofthe punchings, a sheet-like bottom enclosure-member extending over thebottom portions of the two frame-rings for defining a lower annularventilating-space between said bottom enclosure-member and the peripheryof the punchings, outlet-means for providing outlets, in

the vicinity of the two lowermost thick framebars, respectively, fordischarging air from the ends of the top and bottom enclosure-members,along the sides of the machine, below the centerline of thestator-punchings, and a plurality of radially thin, axially extending,punching-retaining means, secured to the outer periphery of the stack ofstator-punchings at intermediate points between the thick frame-bars,for preventing axial spreading of said stack while permitting annularair-flow in radial spaces between said thin punching-retaining means andthe associated enclosure-member.

7. The invention as defined in claim 5, characterized by the stack ofstator-punchings having one or more radial ventilating-openings therein,and said rotormember having one or more corresponding radialventilating-openings therein, and one or more central axial ductstherethrough, whereby ventilating-air flows radially outwardly throughsaid radial ventilatingopenings and then distributes itself axially andcircumferentially in said annular ventilatingspaces on its way out tosaid outlet-means.

8. The invention as defined in claim 6, char- :terized by the stack ofstator-punchings having one or more radial ventilating-openings therein,and said rotor-member having one or more corresponding radialventilating-openings therein, and one or more central axial ductstherethrough, whereby ventilating-air fiows radially outwardly throughsaid radial ventilatingtheir ends secured to said frame-rings.

12. The invention as defined in claim 4, characterized by said thin,axially extending, punchlug-retaining means being frame-bars havingtheir ends secured to said frame-rings.

13. The invention as defined in claim 5, characterized by saidthin,'axially extending, punching-retaining means beingframe-bars havingtheir ends secured to said frame-rings.

14. The invention as defined in clairn'6, ic haracterized by said thin,axially extending. punch ing-retaining means being frame-bars havingtheir ends secured to said frame-rings.

15. A horizontal-shaft dynamo-electric machine having a stator-memberand a rotor-member; said stator-member comprising a stack of annularstator-punchings having a substantially cylindrical outer periphery, andhaving a bore defining an air gap surrounding the rotormember,stator-windings carried by the statorpunchings near the bore thereof, aplurality of radially thick punching-holding frame-bars extendingaxially across the outer periphery of said stack oi stator-punchings andextending beyond both ends of the stack, only one of said thickframe-bars being in the region extending from the top to a point belowthe centerline of the stack of stator-punchings on either side thereof,and that one being at the top, an annular frame-ring secured to the endsof the plurality of thick frame-bars at each end of the machine, saidframe-rings having a substantially annular outer periphery which issubstantially flush with the outer surfaces of the thick frame-bars, anend-bracket secured to each frame-ring, each end-bracket having abearing-member for supporting the rotor-member, and having one or moreinlet-openings for ventilating-air, ventilating-means for causingventilating-air to enter through said inlet-openings at the respectiveends of the machine and to flow radially outwardly over the end-turns ofthe stator-windings and thence to flow radially outwardly past the endportions of the frame-bars where they extend between the end of thestack of statorpunchings and the frame-ring at that end of the machine,a sheet-like top enclosure-member extending over the top frame-bar andthe top portions of the two frame-rings for defining an upper annularventilating-space between said top enclosure-member and-the periphery ofthe punchings, a sheet-like bottom enclosure-member extending over thebottom portions of the two frame-rings for defining a lower annularventilating-space between said bottom encloii sure-member and theperiphery oi the punchings, and outlet-means for providing outlets, below the'centerline of the statorpunehings, for discharging air from theends of the top and bottom enclosure-members, along the sides of themachine.

16. A horizontal-shaft dynamo-electric ma chine having a stator-memberand a rotor-memher; said stator-. member comprising a steel; oi annularstator-punchings having a substantially cylindrical outer periphery, andhaving a bore defining an air gap surrounding the rotor-member,stator-windings carried by the statorpunchings near the bore thereof,three radially th i: punching-holding iraroe-bars extending axiallyacross the outer periphery of said stack of stator-punchings andextending beyond both ends of the stack, one of said thick frame-barsbeing at the top, and the other two being at the sides below thecenterline of the stator=punch= ings, an annular frame-ring secured tothe ends of the three thick frame-bars at each end of the machine, saidframe-rings having a substantially annular outer periphery which issubstan= tially flush with the outer surfaces of the thi A: frame bars,an end-bracket secured to each frame-ring, each end-bracket having abearingmember for supporting the rotor-member, and having one or moreinlet-openings ior ventilating-air, ventilating-means for causingventilating-air to enter through said inlet-openings at the respectiveends of the machine and to flow radially outwardly over the end-turns ofthe stator-windings and thence to flow radially outwardly past the endportions of the frame-bars where they extend between the end of thestack of stator-punchings and the frame-ring at that end of the machine,a sheet-like top enclosuremember extending over the top frame-bar andthe top portions of the two frame-rings for defining an upper annularventilating-space between said top enclosure-member and the periphery ofthe punchings, a sheet-like bottom enclosure-member extending over thebottom portions of the two frame-rings for defining a lower annularventilating-space between said bottom enclosure-member and the peripheryof the punchings, and outlet-means for providing outlets, in thevicinity of the two lowermost thick frame-bars, respectively, fordischarging air from the ends of the top and bottom enclosure-members,along the sides of the machine, below the centerline of thestator-punchings.

17. A horizontal-shaft dynamo-electric machine having a stator-memberand a rotor-memher; said stator-member comprising a stack of annularstator-punchings having a. substantially cylindrical outer periphery,and having a bore defining an air gap surrounding the rotor-member,stator-windings carried by the stator-punchings near the bore thereof,a, plurality of radially thick punching-holding frame-bars extendingaxially across the outer periphery of said stack of stator-punchings,only one of said thick frame-bars being in the region extending from thetop to a point below the centerline of the stack of stator-punchings oneither side thereof, and that one being at the top, an annular frameringsecured to the ends of the plurality of thick frame-bars at each end ofthe machine, said frame-rings having a substantially annular outerperiphery which is substantially flush with the outer surfaces of thethick frame-bars, an endbracket secured to each frame-ring, eachendbracket having a bearing-member for supporting airlines i152 t therotor-member, and having one or more inletopenlnas for ventilating-air,a sheet lihe top enclosure-member extending over the top framelcar andthe top portions oi two frame-rings for defining an upper annularventilating-space hetween said top enclosure member and the periphery ofthe punchines, a sheet-dike bottom enclosure=meznher extending over thebottom portions of the two for defining a lower annular ventiiat1i;,-space between said bottom enclosure=mernher the periphery of thepunehings, and outlet-nieans for providing outlets, below the centerlineoi the stator-punchings, for discharging air tram the ends of the topand bottom enclosure-members, along the sides of the machine; the steel:of stator-punchings having one or more radial ventilatingopeningstherein, and said rotor meniber having one or more corresponding radialventilating openings therein, and one or more central axial ductstherethrough, whereby ventilating-air flows radially outwardly throughsaid radial venmating-openings and then distributes itself axially andcircumierentially in said annular ventilating-spaces on its way out tosaid outletmeans.

18.- A horizontal-shaft dynamo-electric machine having a statonmemherand a rotor-memher; said stator-member comprising a stack of annularstator-punchings having a substantially cylindrical outer periphery, andhaving a bore deflning'an air gap surrounding the rotor-memher,stator-windings carried by the stator-punchlngs near the bore thereof,threeradially thick punching-holding frame-bars extending axially acrossthe outer periphery of said stack of stator punchings, one of said thickframe-bars being at the top. and the other two being at the sides belowthe centerline of the stator-punchings, an annular frame-ring secured tothe ends of the three thick frame-bars at each end of the machine, saidframe-rings having a substantially annular outer periphery which issubstantially flush with the outer surfaces of the thick framebars, anend-bracket secured to each frame-ring, each end-bracket having abearing-member for supporting the rotor-member, and having one or moreinlet-openings for ventilating-air, a sheetlike top enclosure-memberextending over the top frame-bar and the top portions of the twoframerings for defining an upper annular ventilatingspace between saidtop enclosure-member and the periphery of the punchings, a sheet-likebottom enclosure-member extending over the bottom portions of the twoframe-rings for defining a lower annular ventilating-space between saidbottom enclosure-member and the periphery of the punchings, andoutlet-means for providing outlets, below the centerline of thestator-punchings, for discharging air from the ends of the top andbottom enclosure-members, along the sides of the machine; the stack ofstator-punchings having one or more radial ventilating-openings therein,and said rotor-member having one or more corresponding radialventilating-openings therein, and one or more central axial ductstherethrough, whereby ventilating-air flows radially outwardly throughsaid radial ventilatingopenings and then distributes itself axially andcircumferentially in said annular ventilatingspaces on its way out tosaid outlet-means.

19. A horizontal-shaft dynamo-electric ma.- chine having a stator-memberand a rotor-memher; said rotor-member having fan-means for drawing inair, at both ends of the machine, for ventilating purposes; saidstator-member com- 13 prising a stack of annular stator-punchings havinga substantially cylindrical outer periphery, and having a bore definingan air gap surrounding the rotor-member, stator-windings carried by thestator-punchings near the bore thereof, a plurality of radially thickpunching-holding framebars extending axially across the outer peripheryof said stack of stator-punchings and extending beyond both ends of thestack, only one of said thick frame-bars being in the region extendingfrom the top to a point below the centerline of the stack ofstator-punchings on either side thereof, and that one being at the top,an annular frame-ring secured to the ends of the plurality of thickframe-bars at each end of the machine, said frame-rings having asubstantially annular outer periphery which is substantially fiush withthe outer surfaces of the thick framebars, an end-bracket secured toeach frame-ring, each end-bracket having a bearing-member for supportingthe rotor-member, and having one or more inlet-openings forventilating-air, and having baffle-means carried by each end-bracket forcausing at least some of the inlet-air to enter the rotor fan-means atthat end of the machine and to flow thence radially outwardly over theend-turns of the stator-windings and thence to flow radially outwardlypast the end portions of the frame-bars where they extend between theend of the stack of stator-punchings and the frame-ring at that end ofthe machine, a sheetlike top enclosure-member extending over the topframe-bar and the top portions of the two frame-rings for defining anupper annular ventilating-space between said top enclosure-member andthe periphery of the punchings, a sheet-like bottom enclosure-memberextending over the bottom portions of the two frame-rings for defining alower annular ventilating-space between said bottom enclosure-memberandthe periphery of the punchings, and outlet-means for providingoutlets, below the centerline of the stator-punchings, for dischargingair from the ends of the top and bottom enclosure-members, along thesides of the machine. 7

20. A horizontal-shaft dynamo-electric machine having a stator-memberand a rotor-memher; said rotor-member having fan-means for drawing inair, at both ends of the machine, for

the stator-punchings near the bore thereof, three a radially thickpunching-holding frame-bars extending axially across the outer peripheryof said stack of stator-punchings and extending beyond both ends of thestack, one of said thick framebars being at the top, and the other twobeing at the sides below the centerline of the statorpunchings, anannular frame-ring secured to the ends of the three thick frame-bars ateach end of the machine, said frame-rings having a substantially annularouter periphery which is substantially flush with the outer surfaces ofthe thick frame-bars, an end-bracket secured to each frame ring, eachend-bracket having a bearing-member for supporting the rotor-member, andhaving one or more inlet-openings for ventilating-air, and havingbaflle-means carried by each end-bracket for causing at least some ofthe inlet-air to enter the rotor fan-means at that end of the machineand to fiow thence radially outwardly over the end-turns of thestatorwindings and thence to flow radially outwardly past the endportions of the frame-bars where they extend between the end of thestack of stator-punchings and the frame-ring at that end of the machine,a sheet-like top enclosure-member extending over the top frame-bar andthe top portions of the two frame-rings for defining an upper annularventilating-space between said top enclosure-member and the periphery ofthe punchings, a sheet-like bottom enclosure-member extending over thebottom portions of the two frame-rings for defining a lower annularventilating-space between said bottom enclosuremember and the peripheryof the punchings, and outlet-means for providing outlets, in thevicinity of the two lowermost thick frame-bars, respectively, fordischarging airfrom the ends of the top and bottom enclosure-members,along the sides of the machine, below the centerline of thestator-punchings.

FRANCIS J. JOHNS.

No references cited.

